Aquarium filter cartridge



FIG. 1 is a front perspective view of an aquarium filter cartridge showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a side elevational view thereof, the side opposite being identical in appearance; and

FIG. 5 is a bottom plan view thereof. 

The ornamental design for an aquarium filter cartridge, and described as shown. 